1. Field of the Invention
The present invention relates to a robot apparatus, and specifically relates to an articulated robot apparatus having a learning function, that is, the function of calculating a learning correction value to improve the operation of a robot.
2. Description of Related Art
Robots having a learning function, that is, the function of generating a learning correction value to improve the operation of the robot by repetition of the specific operation of the robot are known. Also, when teaching and correcting the operation based on the generated learning correction value, while the robot is being operated, there is a proposed method in which the speed of the robot is reduced to a safe level and the learning correction value is made zero, in order to prevent a situation in which an incorrect learning correction value is applied to the corrected operation (for example, Japanese Unexamined Patent Publication (Kokai) No. 2011-192267, hereinafter called “patent document 1”).
Patent document 1 proposes measures against an exception process in the learning or actual operation of a robot having a learning control function, and a method for relearning. The patent document 1 also proposes a method in which, when teaching and correcting the operation, if a correction amount is within a certain range, a learning correction value of an adjacent position is applied as is. If the correction amount is outside of the certain range, the learning correction value is made zero by deceleration.
However, according to this conventional art, when a learning correction value depends on the position of a to-be-controlled portion of a robot, applying a learning correction value of a different position as-is may interfere with the effect of suppressing vibration. In the case of a large correction amount, a learning correction value is made zero by deceleration, thus interfering with the speed advantage. Also, in systems that perform a tracking operation using a vision sensor or the like, the conventional art cannot be applied to the systems in a situation where the position of a work changes at random.